1. Field of the Invention
The present invention relates in general to automotive air conditioners, and more particularly, to automotive air conditioners of a type which is equipped with means for stopping or at least minimizing conveyance of condensed waterdrops, which have been produced on and dripped from cooling elements of an evaporator of the air conditioner, toward a passenger room.
2. Description of the Related Art
In order to clarify the task of the present invention, a known automotive air conditioner 100 of the above-mentioned type will be discussed with reference to FIG. 10 of the accompanying drawings.
In the drawing, denoted by reference “Dp” is a dash panel of a motor vehicle, which parts an engine room “E” and a passenger room “R”. Denoted by reference “Fp” is a floor panel of the vehicle. Denoted by reference “M” is a fixed cross bar which extends across a front area of the passenger room “R”.
As shown, the air conditioner 100 is supported by the cross bar and comprises a housing in which a generally U-shaped air flow passage “F” is defined.
A cylindrical multiblade fan 11 is installed in an upstream part of the air flow passage “F”. The upstream part constitutes a scroll 12. Downstream of the scroll 12, there is installed a rectangular parallelopiped evaporator 13. The evaporator 13 is inclined with its lowered rear end located just above the lowermost part 14 of the air flow passage “F”. From the lowermost part 14 of the air flow passage “F”, there extends obliquely downward a water drain pipe 15, as shown. A heater core 17 is positioned above the evaporator 13 having a partition wall 16 located therebetween. With this partition wall 16, two parallel passages are defined at a part downstream of the evaporator 13, one being a heater core passage 21A in which the heater core 17 is installed and the other being a bypass passage 21B which bypasses the heater core 17. An air mix door 18 is arranged to control an air flow rate between the heater core passage 21A and the bypass passage 21B. An air mix chamber 21C is defined at a part downstream of the two passages 21A and 21B. That is, to the air mix chamber 21C, both the heater core passage 21A and bypass passage 21B are led. A defrosting air inlet opening 22, a ventilating air inlet opening 23 and a foot warming air inlet opening 24 are defined at a portion downstream of the air mix chamber 21C. The defrosting and ventilating air inlet openings 22 and 23 are controlled by a common door, that is, a ventilation/defrosting door 20. The foot warming air inlet opening 24 is controlled by a foot door 19. The air mix door 18, the foot door 19 and the ventilation/defrosting door 20 shown are of a pivot type, which constitute a pivot type door group “D”.
In operation, air is introduced into the air flow passage “F”by the fan 11 and guided toward the evaporator 13 as is indicated by the thick white arrow. After being cooled by the evaporator 13, the air is turned upward at the lowermost part 14 of the air flow passage “F” and distributed to the two passages 21A and 21B in accordance with the angular position of the air mix door 18. The air thus warmed from the heater core passage 21A and the air from the bypass passage 21B are mixed in the air mix chamber 21C to produce a temperature-conditioned air and distributed to various given portions of the passenger room “R” through the various air inlet openings 22, 23 and 24.
As shown, during this operation, moisture in air from the fan 11 causes an outer surface of the evaporator 13 to collect a condensed water, and when the water on the outer surface exceeds a certain amount, it produces waterdrops “W” falling from the lower edge of the evaporator 13, as shown, which are led into the water drain pipe 15 and discharged to the outside of the vehicle.